1. Field of the Invention
This invention relates to an apparatus for freezing food, and more particularly to a continuous quick freezing apparatus for food capable of obtaining high quality frozen food, such as frozen eat, fish and other types of sea food.
2. Prior Art
Conventional freezing apparatuses may be roughly divided into two types: apparatuses for manufacturing frozen food in windless state, and apparatuses for manufacturing frozen food in airy state.
In the windless freezing apparatus, a one- or two-stage cooling coil is disposed in the top of a freezing case, and copper pressure-fit cooling plates for freezing food are arranged beneath the cooling coils as shelves. A freezing pan is placed on the cooling plate, and the food is placed on the freezing pan. The upper cooling plate moves up and down by means of a hydraulic cylinder; thus, the spacing between the upper cooling plate and the lower cooling plate can be varied.
To freeze food in this type of apparatus, first food is manually placed on the freezing pan. The freezing pan is then placed between the cooling plates. The cooling plate is lowered by a hydraulic cylinder to press tightly there against to freeze the food.
Accordingly, in this apparatus, after freezing is completed, the cooling plate is again raised by the hydraulic cylinder, and each freezing pan placed in each stage is removed. Since the frozen food has a tendency to adhere to the freezing pan, the frozen food must be manually separated from the freezing pan. Thus, job efficiency is very poor. Additionally, since the cooling plates directly contact air, steam in the air is cooled to for frost, which deposits over the entire surface of the cooling plates, lowering the freezing efficiency of the food.
In airy-type freezing apparatuses, cooling coils are provided at both the right and left end walls of the freezing case, and a blower fan is installed between the cooling coils and the inner wall. The air in the case is thus circulated by the fan. A freezing pan conveying belt is provided in the middle part of the case, and a cooling device is installed beneath the conveying belt, so as to freeze the food also from below. This cooling device has cooling coils provided on the copper plate to cool the copper plate, and the conveying belt slides on the copper plate.
In the airy-type freezing apparatus, since the air cooled by the cooling coils is circulated by a fan, the velocity of the air flow against the food is great; thus, drying of the food is promoted. This results in oxidation, which can cause discoloration of eat or fish.
Furthermore, it is necessary to remove the pan to separate the food from the freeing pan, and since this operation is not automated, it is disadvantageous from a labor-saving viewpoint.